Generally, a laundry machine is classified into a pulsator washing machine having an upright drum and a drum type washing machine having a drum laid in a horizontal direction. And, a laundry machine includes a washing machine and a dryer for drying. Moreover, a washer and dryer provided with a drying function belongs a category of the washing device.
In this case, since a drum of the drum type washing machine is laid in a horizontal direction, laundry accommodated within the drum is washed by a falling system.
FIG. 1 and FIG. 2 schematically show a general drum type washing machine according to a related art.
Referring to FIG. 1 and FIG. 2, a drum type washing machine according to a related art includes a body 10, a tub 20 provided within the body 10, a drum rotatably provided within the tub 20 and a driving means for driving the drum 30.
In this case, an entrance 11 for inputting laundry is provided to a front side of the body 10 and a door 40 opening/closing the entrance is provided around the entrance 11.
Besides, a gasket 50 is provided to an inner circumference of the entrance 11 to seal a gap in between the door 40 and the entrance 11.
And, a damper 21 is provided to both lower sides of an outer circumference of the tub 20 to support the tub 20 within the body 10.
Moreover, the driving means includes a drive motor 71 driving the drum 30 and a belt 72 connected to drive a drive force of the drive rotor 71 to the drum 30.
Yet, in the above-explained related art washing machine, water is excessively and unnecessarily consumed in washing laundry that is small and/or less-filthy. In doing so, since the corresponding washing takes the same time required for a general washing course, electricity is unnecessarily consumed as well.
In particular, a laundry soaking prior to performing a washing process is more effective in enhancing washing performance but needs a considerable quantity of water for the laundry soaking. So, the laundry soaking is skipped in a general washing course, whereby it is difficult to obtain optimal washing performance.
Besides, a washing course of the related art washing machine does not include a sterilizing step for sterilizing laundry in addition.
Lately, there is a washing machine configured to have a water heater 60 provided within the tub 20, as shown in the attached drawings to enable a crumb-up washing. Yet, since sterilization of laundry is achieved by a crumb-up course only, it is not preferable that water and power consumptions for the crumb-up course are increased.
So, many efforts have been made to develop and research a new washing device capable of enhancing its washing performance with less water and power consumptions and providing a sterilization function in a manner of spraying high-temperature steam into its drum.
However, in theses related art washing machines provided with the steam spray function may be troubled with safety problems in case of malfunction occurrence. In particular, if there occur a malfunction of a steam generator generating to spray steam, an error in an element that supplies water to the steam generator or drum and the like, damage can be caused to the laundry by the high-temperature steam.
And, the malfunctions or errors of the steam generator or the element configuring the water may overheat the steam generator to reduce the safety of the washing machine itself, thereby triggering additional damages such as fire and the like.
Besides, the same problems are also applicable to a dryer provided with the steam generator.